Plug for upper coupler of trailer

ABSTRACT

A plug for insertion into a through hole of a king pin coupler plate of a trailer includes a body defining an axial direction and having an outer surface defining a perimeter with a distance around the perimeter. A plurality of pliable ears extend from the outer surface. The ears are each individually aligned in the axial direction. The ears each have a width that is less than ten percent of the distance around the perimeter of the outer surface of the body.

BACKGROUND

The present invention relates to a trailer, container and othertransport vehicle and, more particularly, to an upper coupler or “kingpin” of such a trailer, container or transport vehicle. The king pincouples the trailer to the truck that tows the trailer. Thevertically-oriented king pin extends through a hole in ahorizontally-oriented upper coupler plate which supports electricallines and air lines that extend between the truck and the trailer. Thesteel upper coupler plate includes other through holes through which theelectrical lines and pneumatic lines may be accessed.

A problem is that objects may fall out of these holes. In particular,the wiring harnesses and pneumatic lines may fall out of the holes. Theexcess wiring may be bundled up and pushed into a rectangular shapedchamber that is inside the hole and at least partially defined by thecoupler plate. As may be readily appreciated, harnesses may occasionallyfall through the holes and become snagged on the truck, causing warrantyand functionality issues.

Another problem is that foreign objects and materials, such as water,snow, salt, bees, birds, etc., may enter the chamber through theseholes. It has been found that excess moisture and particularly roadsalts cause corrosion inside of the couplers. It has also been foundthat bees, birds, and other pesky animals like to make their homesinside of these holes. This causes a hassle when the trailer has to beworked on, especially in the front area.

SUMMARY

The present invention may provide a plastic plug that is easilyinstalled into a through hole in the upper coupler plate associated withthe king pin of a trailer. The plug may be pushed into the hole from theunderside of the coupler plate.

The plug may have three triangular and axially oriented ears that arespaced apart by 120 degrees around the circumference of the plug. As theplug is pushed into the hole in the steel coupler plate, the threetriangular ears are compressed by the circular edge of the hole. As theplug is pushed slightly farther through the hole, the ears may “pop out”or snap into place once they clear the edge of the hole. Thus, the earsprevent the plug from falling out through the hole in the directionopposite to the direction in which the plug was pushed through the hole.Farther upward movement of the plug may be prevented by the top of theplug running into or engaging a top steel plate that is above andparallel to the coupler plate. Movement of the plug in sideways orlateral direction may be prevented by the roughly quarter inch length ofthe plug that is still inside the hole through which the plug waspushed. The plug may be removed from the chamber and from the hole byprying the edges of the plug with a screwdriver or similar object inorder to bend the triangular ears out and around the steel coupler plateor bottom plate.

In addition to having the ears, the inventive plug is also differentfrom other known plugs in that the inventive plug does not have a flangeat its bottom end. Known plugs have a flange that would extend beyondthe bottom of the steel coupler plate. This extension of the plug wouldinterfere with, or be scraped, by the truck's fifth wheel, which glidesor pushes underneath the coupler plate when coupling with the trailer.Anything that extends beyond the bottom of the hole would snag on thetruck during the coupling process and/or during operation of the truckand trailer.

The invention comprises, in one form thereof, a plug for insertion intoa through hole of a king pin coupler plate of a trailer. The plugincludes a body defining an axial direction and having an outer surfacedefining a perimeter with a distance around the perimeter. A pluralityof pliable ears extend from the outer surface. The ears are eachindividually aligned in the axial direction. The ears each have a widththat is less than ten percent of the distance around the perimeter ofthe outer surface of the body.

The invention comprises, in another form thereof, a plug for insertioninto a through hole of a king pin coupler plate of a trailer. The plugincludes a cylindrical body defining an axial direction and having acylindrical outer surface with a circumference. A plurality of pliableears extend from the outer surface. The ears are each individuallyaligned in the axial direction. The ears each have a width that is lessthan ten percent of the circumference of the outer surface of thecylindrical body. The ears are offset from a bottom end of thecylindrical body. A frusto-conical portion is attached to an upper endof the cylindrical body and tapers toward an upper end of thefrusto-conical portion.

The invention comprises, in yet another form thereof, a trailerarrangement including a king pin coupler plate having an upper surfaceand a through hole. A top plate is mounted substantially parallel to andabove the coupler plate. A bottom surface of the top plate is separatedfrom the upper surface of the coupler plate. A plug engages the bottomsurface of the top plate. The plug includes a body defining an axialdirection and having an outer surface defining a perimeter with adistance around the perimeter. The body has a bottom portion received inthe through hole of the coupler plate. A plurality of pliable earsextend from the outer surface of the body. The ears are eachindividually aligned in the axial direction. The ears each have a widththat is less than ten percent of the distance around the perimeter ofthe outer surface of the body. A bottom end of each ear engages theupper surface of the coupler plate.

An advantage of the present invention is that the plug installed in thecoupler plate may prevent wires and other objects from falling throughthe holes.

Another advantage of the present invention is that the plug does notinclude any portion that extends beyond the bottom of the coupler plate,such as a flange, which could be snagged by moving parts under thecoupler plate.

Yet another advantage of the present invention is that the ears of theplug prevent the plug from falling through the through hole that isbeing plugged. Yet the ears are small and flexible enough to allow theplug to be removed from the through hole from the bottom.

BRIEF DESCRIPTION OF THE DRAWINGS

The above mentioned and other features and objects of this invention,and the manner of attaining them, will become more apparent and theinvention itself will be better understood by reference to the followingdescription of an embodiment of the invention taken in conjunction withthe accompanying drawings, wherein:

FIG. 1 is a perspective view of one embodiment of a plug of the presentinvention;

FIG. 2 is a top view of the plug of FIG. 1;

FIG. 3 is a bottom view of the plug of FIG. 1;

FIG. 4 is a side view of the plug of FIG. 1;

FIG. 5 is a cross-sectional view along line E-E in FIG. 4;

FIG. 6 is a perspective view of one embodiment of a plug of the presentinvention inserted into a coupler plate;

FIG. 7 is a fragmentary perspective view of the coupler plate of FIG. 6mounted on a trailer;

FIG. 8 is perspective view of another embodiment of a plug of thepresent invention;

FIG. 9 is a front view of the plug of FIG. 8;

FIG. 10 is a side view of the plug of FIG. 8;

FIG. 11 is a cross-sectional view along line F-F in FIG. 10;

FIG. 12 is a top view of the plug of FIG. 8;

FIG. 13 is a bottom view of the plug of FIG. 8;

FIG. 14 is perspective view of yet another embodiment of a plug of thepresent invention;

FIG. 15 is a front view of the plug of FIG. 14;

FIG. 16 is a side view of the plug of FIG. 14;

FIG. 17 is a cross-sectional view along line F-F in FIG. 16;

FIG. 18 is a top view of the plug of FIG. 14; and

FIG. 19 is a bottom view of the plug of FIG. 14.

Corresponding reference characters indicate corresponding partsthroughout the several views. Although the drawings representembodiments of the present invention, the drawings are not necessarilyto scale and certain features may be exaggerated in order to betterillustrate and explain the present invention. Although theexemplification set out herein illustrates embodiments of the invention,in several forms, the embodiments disclosed below are not intended to beexhaustive or to be construed as limiting the scope of the invention tothe precise forms disclosed.

DETAILED DESCRIPTION

The embodiments hereinafter disclosed are not intended to be exhaustiveor limit the invention to the precise forms disclosed in the followingdescription. Rather the embodiments are chosen and described so thatothers skilled in the art may utilize its teachings.

Referring to the drawings, wherein like numerals indicate like elements,FIG. 1 illustrates one embodiment of a pliable or flexible plug 20 ofthe present invention which may be made of plastic, rubber, or anothersimilarly pliable material. Plug 20 includes a top surface 22, afrusto-conical portion 24, and a cylindrical body portion 26. Evenlyspaced by 120 degrees around the outer surface of cylindrical bodyportion 26 are three triangular ears 28, only two of which are visiblein FIG. 1.

As shown in FIG. 2, an outer diameter of cylindrical body portion 26 maybe about 4.5 inches, and a width of each ear 28 may be about 0.25 inch.Thus, a circumference of cylindrical body portion 26 may be about 14.14inches, and the width of each ear 28 may be less than 2% of thecircumference of cylindrical body portion 26.

As shown in FIG. 3, plug 20 may be hollow with an open bottom end. Thewall thickness of cylindrical body portion 26 may be about 0.125 inch,and the inner diameter of cylindrical body portion 26 may be about 4.25inches.

As shown in FIG. 4, a diameter of top surface 22 may be about 2.01inches, and a radius at the circular edge of top surface 22 may be about0.25 inch. A height of plug 20 may be about 2.68 inches, and a height ofcylindrical body portion 26 may be about 1.16 inches. Frusto-conicalportion 24 may descend down from top surface 22 at an angle of about 52degrees relative to a horizontal direction. Ears 28 may be aligned in,or oriented in, axial directions 46 that are defined by cylindrical bodyportion 26 and that are perpendicular to coupler plate 30 and top plate32.

As best shown in FIG. 4, a width or diameter of plug 20 does notincrease (i.e., is nonincreasing) in axial directions 46 above and belowears 28. That is, a width or diameter of plug 20 either stays the sameor decreases in axial directions 46 above and below ears 28. Notably,plug 20 does not include a flange on its bottom end that might extendbelow through hole 38.

When installed in a trailer, plug 20 may be sandwiched between a couplerplate 30 and a top plate 32. Thus, most of plug 20 may be disposed in achamber 34 defined between coupler plate 30 and top plate 32. However, abottom section of cylindrical body portion 26, having a height of about0.28 inch as indicated at 36, may be received in a through hole 38 incoupler plate 30. Ears 28 may be aligned in, or oriented in, axialdirections 46 that are perpendicular to coupler plate 30 and top plate32.

As shown in FIG. 5, a length of an ear 28 in a radial direction may beabout 0.25 inch. Each ear 28 may be radially aligned with a respectiverib 40 having a length of about 0.38 inch extending radially inward fromthe wall of cylindrical body portion 26.

FIG. 6 illustrates plug 20 inserted into a through hole 38 in couplerplate 30. Other through holes 38 in coupler plate 30 are alsoillustrated. Other plugs 20 may be respectively inserted into each ofthrough holes 38. It is to be understood that top plate 32 is omittedfrom FIG. 6 for clarity of illustration.

FIG. 7 illustrates coupler plate 30 mounted on a trailer 42. A king pin44 extends downwardly through coupler plate 30. The present invention isnot restricted to a trailer, but more broadly relates to theconstruction of cargo containers and transport vehicles, includingtrailer bodies adapted to be hauled by tractor units (not shown). Theterms “trailer”, “container”, “cargo container” and “transport vehicle”are used interchangeably herein and each such term is meant to designatea partially-closed or closed, hollow structure for carrying cargo. Theinvention may also be applied to truck bodies, which may get mounted totrucks directly and are not coupled via a hitch. Although truck bodiesmay not have king pins, they may have through holes which may be pluggedby the plug of the invention.

During use, plug 20 may be inserted into a through hole 38 from thebottom side. Ears 28 and body portion 26 may pliably deform while ears28 pass through through hole 38. Ears 28 may then spring outward andsnap into their unbiased state upon exiting through hole 38. Thus, ears28 engage the upper surface of coupler plate 30 and prevent plug 20 fromfalling down through through hole 38. Plug 20 may be removed fromthrough hole 38 by reaching up through through hole 38 and prying theedges of body portion 26 with a screwdriver or similar tool to therebybend the triangular ears 28 around and out through hole 38.

FIGS. 8-13 illustrate another embodiment of a flexible or pliable plug120 of the invention which may be made of plastic, rubber, or anothersimilarly pliable material. Plug 120 has a generally rectangular shape,which may match the size and shape of a corresponding through hole inthe coupler plate. Plug 120 includes a top surface 122, a pyramidalportion 124, and a rectangular body portion 126. Evenly spaced by 90degrees around the outer surface of rectangular body portion 126 arefour axially-aligned, triangular ears 128.

As shown in FIG. 9, two smaller opposing portions of pyramidal portion124 are oriented at angles of about 35 degrees relative to a verticalplane. A height of rectangular body portion 126 is about 1.00 inch.

As shown in FIG. 10, a radius between top surface 122 and pyramidalportion 124 may be about 0.50 inch. A total height of plug 120 may beabout 2.78 inches. Two larger opposing portions of pyramidal portion 124are oriented at angles of about 16 degrees relative to a vertical plane.Rectangular body portion 126 extends about 0.25 inch below ears 128.

As shown in FIG. 11, a height of ears 128 is about 1.21 inches. The wallthickness of pyramidal portion 124 may be about 0.13 inch. Each ear 128may be radially aligned with a respective rib 140 having a length ofabout 0.38 inch extending inward from the wall of rectangular bodyportion 126.

As shown in FIG. 12, a width of rectangular portion 126 along a smallerside may be about 4.50 inches, and a width of rectangular body portion126 along a larger side may be about 7.00 inches. Thus, the distancearound a perimeter of rectangular body portion 126 may be approximatelybetween 21 and 23 inches. Each ear 128 has a width of about 0.50 inch,and a length of about 0.25 inch. Thus, each ear 128 may have a widththat is less than 2.5% of the distance around a perimeter of rectangularbody portion 126.

As shown in FIG. 13, plug 120 may be hollow with an open bottom end. Aradius between sides of rectangular body portion 126 may be about 1.00inch. A wall thickness of rectangular body portion 126 may be about 0.13inch. Other features of plug 120 are substantially similar to thefeatures of plug 20, and thus are not described in detail herein inorder to avoid needless repetition.

FIGS. 14-19 illustrate yet another embodiment of a flexible or pliableplug 220 of the invention which may be made of plastic, rubber, oranother similarly pliable material. Plug 220 has a generally rectangularshape, which may match the size and shape of a corresponding throughhole in the coupler plate. Plug 220 includes a top surface 222, apyramidal portion 224, and a rectangular body portion 226. Spaced aroundthe outer surface of rectangular body portion 226 are sixaxially-aligned, triangular ears 228.

As shown in FIG. 15, two larger opposing portions of pyramidal portion224 are oriented at angles of about 36 degrees relative to a verticalplane. A height of rectangular body portion 226 is about 1.00 inch.

As shown in FIG. 16, a radius between top surface 222 and pyramidalportion 224 may be about 0.50 inch. A total height of plug 220 may beabout 2.75 inches. Two smaller opposing portions of pyramidal portion224 are oriented at angles of about 30 degrees relative to a verticalplane. Rectangular body portion 226 extends about 0.25 inch below ears228.

As shown in FIG. 17, a height of ears 228 is about 1.23 inches. The wallthickness of pyramidal portion 224 may be about 0.13 inch. Each ear 228may be radially aligned with a respective rib 240 having a length ofabout 0.38 inch extending inward from the wall of rectangular bodyportion 226.

As shown in FIG. 18, a width of rectangular body portion 226 along asmaller side may be about 7.00 inches, and a width of rectangular bodyportion 226 along a larger side may be about 9.00 inches. Thus, thedistance around a perimeter of rectangular body portion 226 may beapproximately between 30 and 32 inches. Each ear 228 has a width ofabout 0.50 inch, and a length of about 0.25 inch. Thus, each ear 228 mayhave a width that is less than 2.0% of the distance around a perimeterof rectangular body portion 226.

As shown in FIG. 19, plug 220 may be hollow with an open bottom end. Aradius between sides of rectangular body portion 226 may be about 1.00inch. A wall thickness of rectangular body portion 226 may be about 0.13inch. Other features of plug 220 are substantially similar to thefeatures of plug 20, and thus are not described in detail herein inorder to avoid needless repetition.

While this invention has been described as having an exemplary design,the present invention may be further modified within the spirit andscope of this disclosure. This application is therefore intended tocover any variations, uses, or adaptations of the invention using itsgeneral principles. Further, this application is intended to cover suchdepartures from the present disclosure as come within known or customarypractice in the art to which this invention pertains.

What is claimed is:
 1. A plug for insertion into a through hole of aking pin coupler plate of a trailer, said plug comprising: a cylindricalbody defining an axial direction and having a cylindrical outer surfacewith a circumference; a plurality of pliable ears extending from theouter surface, the ears each being individually aligned in the axialdirection, the ears each having a width that is less than ten percent ofthe circumference of the outer surface of the cylindrical body, the earsbeing offset from a bottom end of the cylindrical body, wherein a bottomportion of the cylindrical body extends from the ears to the bottom endof the cylindrical body and is sized to be received in the through holeof the king pin coupler plate while the ears touch the coupler plate andthe bottom end of the cylindrical body is in the through hole and doesnot extend beyond a bottom of the through hole; and a frusto-conicalportion attached to an upper end of the cylindrical body and taperingtoward an upper end of the frusto-conical portion.
 2. The plug of claim1 wherein a distance between an upper surface of the frusto-conicalportion and bottom ends of the ears in the axial direction substantiallymatches a distance between an upper surface of the coupler plate and abottom surface of a king pin top plate of the trailer.
 3. The plug ofclaim 1 wherein the ears are each triangular when viewed along a widthdirection of the ear.
 4. The plug of claim 1 wherein the ears each havea height more than two times greater than the width of the ear.
 5. Theplug of claim 1 wherein said plurality of pliable ears include betweenthree and six ears.
 6. The plug of claim 1 wherein the body is pliable.7. A trailer arrangement, comprising: a king pin coupler plate having anupper surface and a through hole; a top plate mounted substantiallyparallel to and above the coupler plate, a bottom surface of the topplate being separated from the upper surface of the coupler plate; aplug engaging the bottom surface of the top plate, the plug including: abody defining an axial direction and having an outer surface defining aperimeter with a distance around the perimeter, the body having a bottomportion received in the through hole of the coupler plate; and aplurality of pliable ears extending from the outer surface of the body,the ears each being individually aligned in the axial direction, theears each having a width that is less than ten percent of the distancearound the perimeter of the outer surface of the body, a bottom end ofeach said ear engaging the upper surface of the coupler plate, whereineach of the ears has the shape of a right triangle when viewed along awidth direction of the ear, with a right angle of the triangle at thebottom of the ear and adjacent to the body.
 8. The arrangement of claim7 wherein the ears each have a width that is less than three percent ofthe distance around the perimeter of the outer surface of the body. 9.The arrangement of claim 7 wherein the plug lacks a flange.
 10. Thearrangement of claim 7 wherein a bottom side of each said ear issubstantially flat and has a length in a direction away from the body,the length being at least 0.125 inch.